Problem: Simplify the following expression: $y = \dfrac{2}{5k + 4} - \dfrac{-k + 8}{5k + 4}$
Answer: Since the expressions have the same denominator we simply subtract the numerators: $y = \dfrac{2 - (-k + 8)}{5k + 4}$ Distribute the negative sign: $y = \dfrac{2 + k - 8}{5k + 4}$ Combine like terms: $y = \dfrac{k - 6}{5k + 4}$